Bioplastics Recycling Options Expand

Although bioplastics are still a very small part of the plastic waste stream, some manufacturers are talking to recyclers about developing recycling processes for their products. NatureWorks, for example, is working with the Association of Post-Consumer Plastic Recyclers to help develop mechanical and chemical recycling processes for its Ingeo materials, as well as end-markets for the recycled plastic, Steve Davies, global director of marketing and public affairs, told us.

Non-recycled petroleum-based plastics are a big problem in landfills. If left untreated, they don't biodegrade for a long time. And if not recycled or converted to fuel or electricity, the energy they contain is wasted. Estimates of how much plastic goes into landfills vary depending on who's measuring, but according to the EPA, only 12 percent of US plastics got recycled in 2010.

Although durable bioplastics can usually be recycled, composting is usually the most common option for food serviceware, such as these plate, bowl, lid and cup prototypes made of NatureWorks' Ingeo bioplastic based on BioAmber building blocks. (Source: NatureWorks)

Bioplastics end-of-life solutions are composting or recycling, depending on whether it's single-use or durable. "Composting plastic turns it back into the CO2 and water it started as, which closes the cradle-to-cradle loop but doesn't give an opportunity for re-use," said Davies. "This makes sense in compostable food packaging and food serviceware. Since no one sorts the food waste from the plastic waste for recycling, it all goes to the landfill anyway, where compostable materials can biodegrade. Many food serviceware plastic makers now have a compostable version."

Durable bioplastics aren't compostable, and are harder to recycle than single-use bioplastics, Kent Furst, industry analyst for the Freedonia Group, said in an interview. "First, they are often made durable by adding reinforcing agents and fillers, and these can interfere with the recycling process. Second, sometimes the bioplastic is made durable by being blended with conventional plastics, and it becomes difficult to separate the materials for recycling."

Actually, most higher-performance engineering plastics are tough to recycle, bio-based or not, because of the potential for contamination, which can drastically reduce the recycled resin's desirable properties. "So special handling, such as for scrap, is required for high-performance plastics if they are to be recycled into a material that has properties similar to the original," said Furst. "These guidelines for special handling and processing must be made available to recyclers. Some durable bioplastic vendors are addressing these problems by providing the relevant information to their processor customers."

The new range of materials made out of recyclables is opening up huge design possibilities. It's interesting to note that, right now, this is really taking just a drop in the bucket out of the waste stream. In 50 years, however, we could see a significant reduction in the waste stream because of serious percentages of recylcing. As well, the whole movement, notable in the auto industry, about designing equipment so that it's easily disassembled, will reach full flower and feed into this. Also of note is the fact that what's happening now seems driven more by technology than regulations, which makes it more organic.

Seems there are two interesting aspects of this story, Ann. for one, it's good to see a manufacturer would work with a recycler to make sure the products they produce have a welcome home at their end of life. It's also good to see these products will break down easily in landfills -- given that you say 88 percent of plastic doesn't get recycled.

Rob, Completely agree with you and it seems like those two criteria will ultimately become requirements for almost all types of recycling options. It's amazing to think about the amount of innovation that will likely occur in this market area over the next few years, given the pace of developments at this point. Good stuff, Ann.

Thanks for the feedback guys. Actually, only some bioplastics are biodegradable--but purposeful, managed composting and biodegrading in landfills are two different things. The first captures as much CO2 as possible, while the second does not--landfills are the last resort that everyone is trying to avoid because it takes so long for anything to break down there and lets off a lot of CO2 into the atmosphere. Engineering bioplastics are neither, so recycling them is the best option.

Alex' point is a good one about technology, not regulations, driving things. That's certainly the case when it comes to energy recovery of plastic by recycling them into fuels, which will be the subject of my May feature.

I agree, Apresher. Given the low participation in recycling, your suggestion of making materials that decompose easily may be a big answer. Now that we're harvesting methane from landfills, decomposable trash going to landfills will become positive.

But, like everything else, recycling begins in the home. Our fast paced and often immoral life-style seems to be endangering the original concept of home. We now rely government, industry, science, and big thinking to solve the simplest problems that use to be second nature in the home.

Chuck, it is possible to recycle plastics into fuels, which is the subject of my upcoming May feature article on alternative energy. However, bioplastics aren't currently a large component in such recycled plastics-based fuel, since they represent such a small part of the plastics waste stream and since plastics-to-oil technology is only just starting to take off commercially. But yes, you can start with either biomaterials or petromaterials to get to ethanol, and this is happening in small numbers.

It's true that some energy harvesting is occurring at landfills, but it's important to remember that there's a world of difference in CO2 released between unmanaged biodegradation in the typical landfill or anywhere else on the one hand, and managed composting in landfills or anywhere else, on the other. A biodegradable material can take many many years to finish biodegrading, during which time it releases considerable amounts of CO2 and may also leave undesirable residues in the soil. Composting, when done right, happens a lot faster, capturing more CO2 and leaving little or (preferably) no residues.

There are many places on the web to find our more, but here's some info and definitions from BASF, a bioplastics maker:

Many of the new adhesives we're featuring in this slideshow are for use in automotive and other transportation applications. The rest of these new products are for a wide variety of applications including aviation, aerospace, electrical motors, electronics, industrial, and semiconductors.

A Columbia University team working on molecular-scale nano-robots with moving parts has run into wear-and-tear issues. They've become the first team to observe in detail and quantify this process, and are devising coping strategies by observing how living cells prevent aging.

Many of the new materials on display at MD&M West were developed to be strong, tough replacements for metal parts in different kinds of medical equipment: IV poles, connectors for medical devices, medical device trays, and torque-applying instruments for orthopedic surgery. Others are made for close contact with patients.

Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.